Profile forming of pre-pressed wood-strand preforms

Profile forming of wood-strand composites requires an understanding of the forming characteristics of the preforms prior to curing. The profile forming behavior of the pre-pressed preforms was studied with single-curvature V-bending and the thickness recovery of the preforms was measured. Three failure types were identified based on the primary failure mechanisms in V-bending: buckling and shear slip. As an important indicator of the forming defects (thinning and buckling), the initial failure in V-bending was predicted with a strength-based model. The effects of preform conditions on forming characteristics were examined with a response surface model. An understanding of the relationship between preform characteristics and potential defects during profile forming prior to the final curing stage will facilitate development of the underpinning science of profile forming of wood-strand composites.